RE: Just about

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Lau, Gary" <gary.lau-at-hp-dot-com> 


1) Re. can't you just modify your existing primary - You can use your
existing copper tubing, but it must be reshaped into a flat disk.  The
configuration you have now puts it too close to the top of the
secondary, and the pri-sec coupling will be too high.  This would result
in so-called racing sparks across the surface of the secondary, and will
quickly destroy it.

2) Re. safety gap for the NST - the safety gap is between each of the HV
secondary terminals and the NST case, so there are actually two pairs of
gap electrodes.  Ideally, the electrodes should be small spheres, never
sharp or pointy.  I use metal drawer knobs.  The point of the safety gap
is that you WANT the gap to arc should the terminal voltage get too
high.  Attempting to insulate (what?) with a plastic sheet won't help.

3) Re. grounding - there is some controversy here.  My belief is that
the NST case should go to the same RF ground as the secondary base.  Not
sure what you mean re. the NST's normal grounding, but it should NOT
connect to the AC 3rd wire ground.

4) Re. "The holes are in the parts of the PVC that are not coiled" - OK,
this is probably fine then.  I was afraid that you were using perforated
PVC drainage pipe with holes every few inches.

Regards, Gary Lau
MA, USA


Original poster: Nir Weingarten <nirzvi-at-yahoo-dot-com>

This message is in response to Lau Gary's, John
Richardson's and Tristan Steele's messages

Cheers everyone
and thank you all for your great help

In this re-comment I will refer to some of the issues
that you have all mentioned:

  > first, I would consider
  > losing your entire primary design... Stick with a
  > flat pancake design

  > the primary
  > should be a flat spiral at the base of the
  > secondary

Got it. but what exactly should I do? is it crucial,
and cant I just modify my existing primary?

  > Place a safety gap across your NST.  A piece of
  > wire
  > from each NST terminal to the NST case, with about
  > 1/4 inch spacing
  > between
  > the two, should suffice.

Terry Fritz mentioned it to me once... what exactly
should I do and with which terminals (even the input)?
And is it crucial, cant I simply locate a peace of
plastic shielding my NST?

  > And to answer your grounding question, ground
  > the
  > NST and the bottom of the secondary to a pipe driven
  > into the ground

Thats just about what I've figured, but should I
connect both groundings to the same pipe? and should I
ground the NST through its 'normal' grounding?

  > if you have holes in your
  > PVC, this is bad,
  > especially if wire goes through it

, such as the plastic caps at the end or the
PVC's body at the bottom (Like shown in pictures at my
web page). Is it still a problem?

Thanks again, Nir

=====

Best wishes

                                                Nir(NOT NEAR) Weingarten

Israel